using System;
using System.Collections.Generic;
using System.Runtime.CompilerServices;
using Server.Items;
using Server.SkillHandlers;

namespace Server.Spells.Ninjitsu;

public class DeathStrike : NinjaMove
{
    private static readonly Dictionary<Mobile, DeathStrikeTimer> _table = new();

    public override int BaseMana => 30;
    public override double RequiredSkill => 85.0;

    // You prepare to hit your opponent with a Death Strike.
    public override TextDefinition AbilityMessage { get; } = 1063091;

    public override double GetDamageScalar(Mobile attacker, Mobile defender) => 0.5;

    public override void OnHit(Mobile attacker, Mobile defender, int damage)
    {
        if (!Validate(attacker) || !CheckMana(attacker, true))
        {
            return;
        }

        ClearCurrentMove(attacker);

        var ninjitsu = attacker.Skills.Ninjitsu.Value;

        // TODO: should be defined onHit method, what if the player hit and remove the weapon before process? ;)
        var isRanged = attacker.Weapon is BaseRanged;

        var chance = ninjitsu switch
        {
            // This formula is an approximation from OSI data.  TODO: find correct formula
            < 100 => 30 + (ninjitsu - 85) * 2.2,
            _     => 63 + (ninjitsu - 100) * 1.1
        };

        if (chance / 100 < Utility.RandomDouble())
        {
            attacker.SendLocalizedMessage(1070779); // You missed your opponent with a Death Strike.
            return;
        }

        var damageBonus = 0;

        if (_table.Remove(defender, out var timer))
        {
            defender.SendLocalizedMessage(1063092); // Your opponent lands another Death Strike!

            if (timer.Steps > 0)
            {
                damageBonus = (int)(attacker.Skills.Ninjitsu.Value / 15);
            }

            timer.Stop();
        }
        else
        {
            defender.SendLocalizedMessage(1063093); // You have been hit by a Death Strike!  Move with caution!
        }

        attacker.SendLocalizedMessage(1063094); // You inflict a Death Strike upon your opponent!

        defender.FixedParticles(0x374A, 1, 17, 0x26BC, EffectLayer.Waist);
        attacker.PlaySound(attacker.Female ? 0x50D : 0x50E);

        var t = new DeathStrikeTimer(defender, attacker, damageBonus, isRanged);

        _table[defender] = t;

        t.Start();

        CheckGain(attacker);
    }

    public static void AddStep(Mobile m)
    {
        if (_table.TryGetValue(m, out var timer) && ++timer.Steps >= 5)
        {
            timer.ProcessDeathStrike();
        }
    }

    public static void RemoveEffect(Mobile m)
    {
        if (_table.Remove(m, out var timer))
        {
            timer.Stop();
        }
    }

    private class DeathStrikeTimer : Timer
    {
        private Mobile _attacker;
        private int _damageBonus;
        private bool _isRanged;
        private Mobile _target;
        public int Steps { get; set; }

        internal DeathStrikeTimer(Mobile target, Mobile attacker, int damageBonus, bool isRanged)
            : base(TimeSpan.FromSeconds(5.0))
        {
            _target = target;
            _attacker = attacker;
            _damageBonus = damageBonus;
            _isRanged = isRanged;
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        protected override void OnTick()
        {
            ProcessDeathStrike();
        }

        public void ProcessDeathStrike()
        {
            int damage;

            var ninjitsu = _attacker.Skills.Ninjitsu.Value;
            var stalkingBonus = Tracking.GetStalkingBonus(_attacker, _target);

            if (Core.ML)
            {
                var scalar = Math.Min(1, (_attacker.Skills.Hiding.Value + _attacker.Skills.Stealth.Value) / 220);

                // New formula doesn't apply DamageBonus anymore, caps must be, directly, 60/30.
                if (Steps >= 5)
                {
                    damage = (int)Math.Floor(Math.Min(60, ninjitsu / 3 * (0.3 + 0.7 * scalar) + stalkingBonus));
                }
                else
                {
                    damage = (int)Math.Floor(Math.Min(30, ninjitsu / 9 * (0.3 + 0.7 * scalar) + stalkingBonus));
                }

                if (_isRanged)
                {
                    damage /= 2;
                }

                _target.Damage(damage, _attacker); // Damage is direct.
            }
            else
            {
                var divisor = Steps >= 5 ? 30 : 80;
                var baseDamage = ninjitsu / divisor * 10;

                var maxDamage = Steps >= 5 ? 62 : 22;
                damage = Math.Clamp((int)(baseDamage + stalkingBonus), 0, maxDamage) + _damageBonus;

                // Damage is physical.
                AOS.Damage(
                    _target,
                    _attacker,
                    damage,
                    true,
                    100,
                    0,
                    0,
                    0,
                    0,
                    0,
                    0,
                    false,
                    false,
                    true
                );
            }

            RemoveEffect(_target);
        }
    }
}
